Method of and a device for safeguarding a vehicle or machinery movable in space

Abstract

A method of and a device for safeguarding a vehicle or machinery movable in space, such as a robot, a stacker, an operatorless transporting vehicle or the like against collision, in which by the use of distance sensors, especially ultrasonic sensors with echo time measurement, the distance from an obstacle is measured and a reaction signal is initiated when a preset threshold value is not reached, said method and device being characterized by a time-synchronous actuation of the distance sensors in a compound circuit which in case of a dangerous approach of the vehicle to an obstacle triggers a reaction signal which is either a speed reduction signal or a stop signal. Moreover, the measuring signal can be utilized as a command signal for actively influencing the vehicle movement, e.g. for driving around the obstacle or the like.

We claim: 
     
       1. A method of safeguarding a vehicle or machinery movable in space, such as a robot, a stacker, or an operatorless transporting vehicle against collision, wherein by the use of distance sensors, especially ultrasonic sensors with echo time measurement, the distance from an obstacle is measured and a reaction signal for acting on the vehicle movement is initiated when predetermined threshold values are not reached, said method comprising the steps of initiating the distance measurements in time synchronism for all sensors, and jointly processing the obtained measuring signals for producing at least a reaction signal. 
     
     
       2. A method as claimed in claim 1, wherein the measuring signal from one of said distance sensors is utilized as a command signal for actively influencing the vehicle movement. 
     
     
       3. A device for safeguarding a vehicle or machinery movable in space, such as a robot, a stacker, or an operatorless transporting vehicle against collision, wherein, by the use of distance sensors, especially ultrasonic sensors with echo time measurement, the distance from an obstacle is measured and a reaction signal is initiated when predetermined threshold values are not reached, comprising: a time module (20) for initiating the measuring operations of all said distance sensors (40) in time-synchronism, and then clocking the measuring operations of all said sensors,   a comparator module (24, 26) for comparing the measured distance values from the individual distance sensors (40) with the threshold values and providing the reaction signal when said threshold values are not reached,   an output module for identifying a triggering one of said distance sensors and an interface (36) for converting the reaction signal to a signal for influencing the drive unit of the system.   
     
     
       4. A device as claimed in claim 3, wherein each distance sensor (40) is an ultrasonic sensor and is interconnected with a sensor module (22) for initiating and pre-processing of the measuring signal. 
     
     
       5. A device as claimed in claim 3, wherein the threshold values can be preset in the comparator module (24, 26) either individually, in groups, or jointly so as to be identical for all distance sensors, and said threshold values are variable. 
     
     
       6. A device as claimed in claim 3, wherein said comparator module comprises two submodules, one submodule containing predetermined threshold values for a speed reduction signal and the other one containing predetermined threshold values for a stop signal. 
     
     
       7. A device as claimed in claim 3, wherein the threshold values are inputted into the comparator module (24, 26) via an encoding switch (30) or by radio. 
     
     
       8. A device for safeguarding a vehicle or machinery movable in space, such as a robot, a stacker, or an operatorless transporting vehicle against collision, wherein, by the use of ultrasonic sensors with echo time measurement, the distance from an obstacle is measured and a reaction signal is initiated when predetermined threshold values are not reached, comprising a receiving means fixed on the vehicle (2) for adjustably mounting said sensors at presettable angles, said receiving means having means for interchangeably mounting a directional horn and an adjusting projection for presetting said angles. 
     
     
       9. A device as claimed in claim 8, wherein the receiving means is designed for receiving a plurality of individually adjustable ultrasonic sensors (40) and a sensor module common to said ultrasonic sensors, said sensor module being an electronic module (62). 
     
     
       10. A device as claimed in claim 8, wherein the receiving means includes a housing (46) having a bore (44) for exchangeably accommodating a spherical swivel head (42) which contains the ultrasonic sensor (40) and after adjustment by means of screws (50) can be fixed in the adjusted position in the housing (46). 
     
     
       11. The method as defined in claim 1 wherein said distance measurements are initiated simultaneously. 
     
     
       12. The device as defined in claim 3 wherein said measurement operations are initiated simultaneously. 
     
     
       13. A device as claimed in claim 10, wherein the swivel head (42) is designed to provide for capacitive decoupling of the ultrasonic sensor (40) from the housing (46). 
     
     
       14. A device as claimed in claim 4, wherein the threshold values can be preset in the comparator module (24, 26) either individually, in groups, or jointly so as to be identical for all distance sensors, and said threshold values are variable. 
     
     
       15. A device as claimed in claim 6, wherein the threshold values are inputted into the or each comparator module (24, 26) via an encoding switch (30) or by radio. 
     
     
       16. A device for safeguarding a vehicle movable in space against collision comprising: plural ultrasonic sensors capable of measuring the distance from the vehicle to an obstacle; and   receiving means for adjustably mounting said ultrasonic sensors at predetermined angles relative to the vehicle, said receiving means comprising: a housing having a bore for accommodating an adjustably directed swivel head containing one of said ultrasonic sensors,   said swivel head having a projection for removably receiving an adjusting device for positioning said head and thereby the ultrasonic sensor contained therein, at one of said predetermined angles.     
     
     
       17. The device as defined in claim 16 wherein said projection interchangeably receives a directional horn and said adjusting device. 
     
     
       18. A method of safeguarding a vehicle movable in space against collision with an obstacle, said vehicle having a plurality of sensors for emitting signals related to determining the distance from the vehicle, comprising the steps of: (a) transmitting said signals from all said sensors simultaneously;   (b) receiving reflections of said signals that are reflected from an obstacle back to said vehicle; and   (c) jointly processing said reflections by: (i) measuring the elapsed time between transmitting said signals and the time of receipt of said reflections,   (ii) making a first comparison of said measured elapsed time to a first predetermined elapsed time threshold,   (iii) generating a first reaction signal responsively to said first comparison for stopping said vehicle when said measured elapsed time is less than said first threshold,   (iv) making a second comparison of said measured elapsed time to a second predetermined elapsed time threshold, and   (v) generating a second reaction signal responsively to said second comparison for slowing the speed of said vehicle when said measured elapsed time is less than said second threshold.     
     
     
       19. A device for safeguarding a vehicle movable in space against collision with an obstacle comprising: plural sensors for emitting signals and for receiving reflections of said signals from an obstacle;   a time module for triggering all of said sensors to emit said signals simultaneously and for determining elapsed time between triggering of all said sensors and time of receipt of said reflections by each of said sensors;   a first comparator module for comparing said determined elapsed time to a first predetermined threshold, said first predetermined threshold being a first predetermined elapsed time from the triggering of all said sensors;   a first signalling means for generating a first reaction signal responsively to said first comparator for stopping the vehicle when said determined elapsed time is less than said first threshold;   a second comparator module for comparing said determined elapsed time to a second predetermined threshold, said second predetermined threshold being a second predetermined elapsed time from the triggering of all said sensors longer than said first predetermined elapsed time;   a second signalling means for generating a second reaction signal responsively to said second comparator for slowing the speed of the vehicle when said determined elapsed time is less said second threshold; and   means for adjusting said first and second thresholds in said first and second comparators, respectively, for each of said sensors, whereby said first and second thresholds may be the same for all said sensors or different for each of said sensors.   
     
     
       20. The device as defined in claim 3 wherein one of said threshold values is set to enable said comparator module to provide a reaction signal when the distance to an obstacle is approximately ten meters. 
     
     
       21. The device as defined in claim 19 wherein said second predetermined elapsed time relates to a ten meter distance to an obstacle.